Pastas are produced by adding water to wheat flour, kneading the mixture to prepare a dough of firm consistency and shaping the dough by extrusion through an extruder or the like under high pressure. Typically, the semolina of durum which is a hard wheat (or high gluten content) is used as a primary raw material, which is occasionally mixed with egg white, milk and other ingredients. The pastas thus produced are in hard and dense shapes. Pastas are prepared by boiling and are cooked to provide a moisture gradient such that the moisture content in the center of the pasta is lower than the surface moisture content; the pastas are said to taste best when served "al dente" with a "firm" texture.
To create the "al dente" condition, the use of dry or raw pastas is preferred; however, these pastas take a long time to boil and are unsuitable for the case where convenience and speed in cooking are required.
Several methods have been attempted to serve pastas "al dente" with improved convenience and speed in cooking, including providing V cuts along the strings of pastas such as spaghetti or quickly freezing pastas that have been boiled "al dente". However, even the pastas with V cuts cannot be cooked as quickly and conveniently as "instant noodles". Frozen pastas have no problems with quality but because of the limitations in distribution and storage on the market, they have not become as popular as "instant noodles".
As for noodles including Japanese noodles such as udon, soba, hiyamugi and kishimen and Chinese noodles, various methods have also been proposed to accomplish the manufacture of quick boiling products. According to the known proposals, partially cooked noodles prepared by boiling raw noodles for a short time or boiled products prepared by boiling raw or dry noodles are distributed either chilled or frozen. However, these partially cooked noodles or preboiled noodles have had the problem that during the distribution, not only their palatability deteriorates but also the strings become "too tender" with the lapse of time, thereby deteriorating in texture.
Various types of "instant noodles" are manufactured and sold on the market. They are produced by either frying raw noodles with oil or fats or steaming them followed by drying. However, either type of product has the disadvantage that when cooked, the noodles do not have as firm a texture as the products prepared by boiling dry or raw noodles.
Under the circumstances, it has been desired to develop instant cooking pastas or noodles that are easy to manufacture, that can be cooked and served "al dente" or with firm consistency by merely boiling up in hot water for a short cooking time, say, within three minutes or by just heating in a microwave oven.